Az ATA-3 (X3T132008D rev7b) szabvány -ahol a SMARTot definiálták- ezt írja:
6.6 Self-monitoring, analysis, and reporting technology
6.6.1 Attributes
Attributes are the specific performance or calibration parameters that are used in analyzing the status of the device. Attributes are selected by the device manufacturer based on that attribute’s ability to contribute to the prediction of degrading or fault conditions for that particular device. The specific set of attributes being used and the identity of these attributes is vendor specific and proprietary.
6.6.2 Attribute values
Attribute values are used to represent the relative reliability of individual performance or calibration attributes. The valid range of attribute values is from 1 to 253. Higher attribute values indicate that the analysis algorithms being used by the device are predicting a lower probability of a degrading or fault condition exisiting. Accordingly, lower attribute values indicate that the analysis algorithms being used by the device are predicting a higher probability of a degrading or fault condition existing.
6.6.3 Attribute thresholds
Each attribute value has a corresponding attribute threshold limit which is used for direct comparison to the attribute value to indicate the existence of a degrading or fault condition. The numerical value of the attribute thresholds are determined by the device manufacturer through design and reliability testing and analysis.
Each attribute threshold represents the lowest limit to which its corresponding attribute value can be equal while still retaining a positive reliability status. Attribute thresholds are set at the device manufacturer’s factory and cannot be changed in the field. The valid range for attribute thresholds is from 1 through 253.
A leírtakból világosan látszik, hogy a SMART attribútumnál a nagyobb érték jelzi azt, hogy kisebb a vinyó meghibásodásának esélye.
És a progim is jól működik, mert a szabváyn mellett pl. az ActivSmartnál is akkor van hiba, ha a Value a Treshold értéke alá csökken:
Sokkal kellemesebb úgy hibát keresni, ha tudod, hogy másban kell!
